<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta http-equiv="X-UA-Compatible" content="IE=edge">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Document</title>
</head>
<body>
    <div id="app">
        <p>current time: {{ currentTime1() }}</p>
        <p>current time: {{ currentTime2 }}</p>
    </div>
    <script src="https://cdn.jsdelivr.net/npm/vue@2/dist/vue.js"></script> 
    <script src="https://cdn.jsdelivr.net/npm/axios/dist/axios.min.js"></script>
    <script>
        Vue.component('insert', {
            props:['sin'],
            template: '<li>{{ sin.a }}</li>'
        });
        var vm = new Vue({
            el: "#app",
            methods: {
                currentTime1: function(){
                    return Date.now();
                }
            },
             computed: {
                currentTime2: function(){
                    return Date.now();
                }
            },
        })
    </script>
</body>
</html>